1. Field of the Invention
The present invention relates to an improved structure of a stapler, in particular, to a stapler having a slidable cartridge which allows loading of multiple units of staples into the stapler.
2. Description of the Prior Art
A conventional stapler essentially consists of an upper shell, an intermediate slotting seat, a sliding seat and a bottom seat. Normally, only a single unit of staples is loaded onto the slotting seat. An urging plate is vertically and downwardly mounted at the front end of the upper shell. A pair of guiding ends are formed at the front end of the slotting seat so as to block the staples when they are urged to the front end by the sliding seat. The urging plate presses a staple from the top thereof into an object to be stapled. When the staples in the slotting seat have been used up and a new unit is to be loaded, the upper shell of the stapler has to be lifted up and the sliding seat has to be pushed backward to the rear end of the slotting seat. After that the new unit of staples is then loaded. Owing to the fact that the front end of the sliding seat is attached to a spring at one end and, and the other end of the spring is secured to a hook provided at the front end of the slotting seat, close to the guiding end, the sliding seat tends to oppose the direction of back ward push and move forward to the guiding end. Thus, when the user lifts up the upper shell and moves the sliding seat with one hand, and the other hand is used to fill a replacement unit of staples, occasionally the insufficient force of the fingers may cause the sliding seat to return to its original position, i.e. to move towards to the guiding end with a great speed. Thus, the fingers of the user may be hurt accidentally. Besides, for this conventional stapler, only one unit of staples can be filled to the slotting seat at a time and it is inconvenient to the user if there are multiples objects need to be stapled.